The occurrence of thrombosis during angiographic procedures is problematic. The anticoagulant properties of the currently available commercial contrast media are questionable. The nonionic contrast media are being investigated for their potential role in a thrombotic event during angiography. The ionic contrast media are thought to have some anticoagulant properties, however, they are less tolerated physiologically by the patient compared to nonionic contrast media. Accordingly, the provision of a contrast media with both anticoagulant properties and good physiological properties would be extremely valuable.
U.S. Pat. No. 3,953,501 to Klieger describes compounds of the formula: 
U.S. Pat. No. 4,264,572 to Klieger et al. describes X-Ray contrast media having the following general formula: 
P. Dawson, Embolic Problems in Angiography, Seminars in Hematology 28, 31-37 (1991), states that anticoagulant activity can not be provided in a non-ionic contrast agent without a general increase in toxicity of that agent.